DOCK4 Correlated with Immune Infiltration is a Valuable Prognostic Biomarker in Stomach Adenocarcinoma.

Abstract Background: Dedicator for cytokinesis 4 (DOCK4), a guanine nucleotide exchange factor (GEF) for the small GTPase Rac1, the mechanisms involved in immune infiltration in STAD (stomachadenocarcinoma) remain unclear. Methods: The UALCAN database was used to analyze the expression of the DOCKfamily, and the Kaplan-Meier plotter and GEPIA databases were used to assess the prognostic value of the DOCK family in STAD. Furthermore,the correlation between DOCK4 expression withtumor immune infiltration and the expression of related immune marker genes in STAD was explored using TIMER and GEPIA websites. Subsequently, the relationship between DOCK4 expression and clinical characteristics was verified using the UALCAN database. Finally, the mutation of DOCK4 was analyzed via TIMER2.0 and cBioPortal databases. And the protein-protein interaction(PPI) networks of DOCK4 were constructed using GeneMANIA and STRING websites. Results: DOCK4 was finally screened out, and its expression in tumors was significantly evaluated relative to paracancerous tissues and had a negative impact on the prognosis of patients with STAD.DOCK4 was found significantly related to tumor immune infiltration in STAD. Conclusions: In summary, DOCK4 is a potential regulator of the recruitment and regulation of immune infiltrating cells, thus becoming a valuable prognosticbiomarker in STAD.